What science calls the "critical temperature," that is, the temperature when a substance shares both the liquid and gaseous states, is symbolic of what philosophical mysticism calls the "philosophic experience," that is, when a man's consciousness shares both the external world of the five senses and the internal world of the empty soul. The ordinary mystic or yogi is unable to hold the two states simultaneously and, quite often, even unwilling to do so, because of the false opposition he has been taught to set up between them.
-- Notebooks Category 20: What Is Philosophy? > Chapter 4: Its Realization Beyond Ecstasy > # 122
-- Perspectives > Chapter 20: What Is Philosophy? > # 53